Hi Alex,

> All functions ignore atomic CDRs of the last argument cell. You could
> also try (onOff A B . X), the 'X' will be simply ignored.

so why is not NIL in the (onOff . NIL) ignored? ;-)

> zero arguments (as in 'onOff') are not to be expected, the function goes
> straight on and "takes" the first argument, which happens to be NIL in
> this case. So 'onOff' does not distinguish (nor even check) the
> difference between
>    (onOff)
> and
>    (onOff NIL)
> There is no practical reason to do so, because calling 'onOff' without
> arguments makes no sense. Remember, it is a non-evaluating function, and
> cannot be called in a less predictable way (e.g. being passed through
> 'apply', mappings etc.).


> I think that most functions in PicoLisp behave like this. Try 'list',
> for example:
>    : (list NIL)
>    -> (NIL)
>    : (list)    
>    -> (NIL)
> It does not care to check for the first argument.

'list' is a good example where I find this behaviour rather strange.

>    : (list)    
>    -> (NIL)

Here I would expect NIL and not (NIL).  Any other lisp I know works this
way and it also makes sense.  I.e.  the command says make a list of
nothing (not even a NIL) and an empty list is NIL so this behaviour
seems broken to me.  Do you have any example or code in picolisp that
takes advantage of this behaviour?

Thank you,

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